Internal combustion engines



Jan. 2, 1968 M. R. SCHOTT INTERNAL COMBUSTION ENGINES 2 Sheets-Sheet 1' Filed June 2'7, 1966 mm mm Q g Jan. 2, 1968 M. R. SCHOTT 3,36

INTERNAL COMBUSTION ENGINES Filed June 27, 1966 2 Sheets-Sheet 2 United States Patent 25, Claims. (ill. 123-4 0) The present invention relates to internal combustion engines including at least one combustion chamber controlled by means of at least one valve. It is more especially, but not exclusively, concerned with such engines working with the four-stroke cycle.

The chief object of the present invention is to provide an engine of this kind which is better adapted to meet the requirements of practice than those known up to this time, especially concerning the conditions in which intake and exhaust take place.

An internal combustion engine, according to the present invention, includes:

First, a hydraulic generator capable of delivering a liquid under pressure in a continuous manner,

Secondly, at least one volumetric receiver, i.e. a receiver operative by variation of the volume of liquid fed thereto, for instance of the cylinder and piston type, fed with liquid under pressure from said generator, said receiver controlling the valve of the internal combustion engine to produce opening thereof against the action of resilient return means urging said valve toward its closed position, and,

Thirdly, a distributor interposed between said hydraulic generator and said receiver and adapted to cause said valve to have an opening motion according to a predetermined law, the movable element of said distributor being driven by the internal combustion engine.

According to the present invention this distributor includes:

At least two rotating elements for controlling liquid feed and liquid discharge, respectively, said rotating, elements being disposed on opposed sides of a stationary element and having slide faces cooperating with opposed slide faces of said stationary element, respectively,

The receiver being operated through two distinct pipes, to wit, a feed pipe starting from the stationary element slide face that cooperates with the rotaing elemen serving to the feed of liquid and a discharge pipe opening into the stationary element slide face that cooperates with the discharge rotating element.

A preferred embodiment of the present invention will be hereinafter described with reference to the appended drawings, given merely by way of example, and in which,

FIG. 1 is a diagrammatic sectional view of the essential elements of a four-stroke internal combustion engine according to the present invention;

FIG. 2 is an explanatory diagram corresponding to FIG. 1;

FIG. 3 shows a curve illustrating the advantages of the present invention.

In the embodiment of the invention illustrated by the drawings, the internal combustion engine is of any type whatever, including a cylinder head i, a cylinder 2 and a combustion chamber 2a.

Cylinder head 1 comprises the following elements:

On the one hand, an intake pipe 3 opening into cylinder 2 through an intake valve 4, and,

On the other hand, an exhaust pipe 5 starting from cylinder 2 through an exhaust valve 6.

3,351,121 iatentetl. Jan. 2, 1968 Intake valve 4 and exhaust valve 6 are controlled by a hydraulic device including the following elements:

First, a hydraulic generator 7 consisting, in the em bodiment illustrated, of a pump capable of delivering liquid under pressure in a continuous manner;

Secondly, as many receivers, of the type including a cylinder and a piston cooperating with said cylinder, as there are valves to be controlled, i.e. in the embodiment illustrated, a receiver 8 cooperating with intake valve 4 and a receiver 9 cooperating with exhaust valve 6, said receivers 3 and 9 causing valves 4 and 6 to open against the action of springs ill and 12, respectively; and,

Thirdly, a distributor it}, interposed between hydraulic generator 7 and hydraulic receivers 8 and 9, arranged in such manner as to cause valves 4 and 6 to open according to predetermined laws, the movable part of said distributor ill being driven by the internal combustion engine.

Hydraulic generator 7 may advantageously be constituted by a gear pump.

Advantageously, the liquid propelled by this pump consists of the lubricating oil of the engine This pump may be mounted either in series with the lubricating pump (not shown) of the engine or in parallel with this pump. It may be constituted by the lubricating pump itself.

Receivers 8 and 5 are advantageously identical and consist each of a piston 13 slidable in a cylinder 14 fed, through distributor 10, from hydraulic generator 7.

Each piston 13 carries an axial rod 15 the free end of which bears upon the tail end of the valve, 4 or 6, that is considered, said axial rod 15 being rigid with a plate 16 supporting a damping disc 17 cooperating with an abutment surface 13 provided for this purpose in the cylinder head it of the engine.

Now, according to the present invention, distributor 10 comprises two pairs of rotary elements, to wit,

A first pair consisting of a feed element 24 and a delivery element 35, these elements being disposed contiguous to, and on opposed sides of, a stationary element 28 having opposed slide faces adapted to cooperate with the respective slide faces of said rotating elements 24 and 35, and

A second pair consisting of a feed element and .a delivery element 36, these elements being disposed contiguous to and on opposed sides of, a stationary element 2% having opposed slide faces adapted to cooperate with the respective slide faces of said rotating elements 25 and 36.

Volumetric receiver 3 communicates with two pipes, to wit,

A feed pipe 48 starting from the slide face of element 23 which cooperates with rotating feed element 24 and discharge pipe 49 opening from the slide face of fixed element 28 that cooperates with the rotating delivery element 35.

Likewise, volumetric receiver 9 communicates with two pipes, to wit,

A feed pipe 50 starting from the slide face of element 29 which cooperates with rotating feed element 25 and discharge pipe 51 opening from the slide face of fixed element 29 that cooperates with the rotating delivery ele ment 3d.

Distributor 10, arranged symmetrically, comprises:

0n the one hand, a portion I for controlling intake valve 4 and including rotating elements 24 and having slide faces adapted to cooperate with corresponding slide faces of stationary element 28, and

,On the other hand, a portion 11 for controlling exhaust valve 6 and including rotating elements 25 and 35 having slide faces adapted to cooperate with corresponding slide faces of stationary element 29.

Portion I of distributor comprises:

On the one hand, a high pressure port 38 provided in feed element 24 and intended to feed liquid, through an arcuate feed orifice 52 provided in the corresponding slide face of stationary element 28, to the feed pipe 48 of intake valve 4, and,

On the other hand, a high pressure port 41 provided in delivery element 35 and intended to receive liquid through an arcuate outlet orifice 53 provided in the corresponding slide face of stationary element 28, from the outlet pipe 49 of said intake valve 4.

In a likewise manner, portion 11 of distributor 10 comprises:

On the one hand, a high pressure port 43 provided in feed element and intended to feed liquid through an arcuate feed orifice 54 provided in the corresponding slide face of stationary element 29, to the feed pipe 50 of exhaust valve 6, and,

On the other hand, a high pressure port 46 provided in delivery element 36 and intended to receive liquid through an arcuate outlet orifice 55 provided in the corresponding slide face of stationary element 29, from the outlet pipe 51 of said exhaust valve 6.

Distributor 10 is connected to hydraulic generator 7 and to a tank 33 containing, for instance, the oil reserve for the internal combustion engine and it comprises the following elements:

A central chamber 21 provided in a casing 22 and permanently fed with liquid from hydraulic generator 7 through a pipe 23;

The two above mentioned rotating feed elements 24 and 25, disposed on either side of this central chamber 21, fixed upon a driving shaft 26 and pushed, by means of a spring 27, respectively against the corresponding faces of elements 28 and 29;

Two end chambers 30 and 31, located at the ends of casing 22 and communicating together through a channel 32 provided in driving shaft 26, these two end chambers 30 and 31 being permanently connected with the engine oil tank 33 through a pipe 34; and

The two above mentioned rotating delivery elements 35 and 36, located respectively in the two end chambers 30 and 31 and secured to driving shaft 26, these elements 35 and 36 cooperating respectively with the corresponding faces of fixed elements 28 and 29, with the interposition of a spring 37.

It will be understood that, in order to obtain the desired laws of upward movement of intake valve 4 and exhaust valve 6 compatible with the four-stroke cycle of the engine, it suffices to displace angularly with respect to each other feed element 24 and 25 and delivery element 35 or 36.

As for the respective dimensions of high pressure ports 38 and 43 and of low pressure ports 41 and 46, they depend of course upon the particular movements of the upwards movements to be imparted to intake valve 4 and exhaust valve 6.

It will be supposed, by way of example, that shaft 6 revolves with an angular speed equal to one half of that of the engine crankshaft.

The left hand side of FIG. 2 shows, in plan view, the liquid feed control rotating element 25, acting on exhaust valve 6, which bears against stationary element 29, said element 25 rotating in the clockwise direction. The angle A of rotation of the internal combustion engine corresponding to the opening of exhaust valve 6 is determined by the respective position of the high pressure port 43 and of the arcuate orifice 54, as indicated by FIG. 2 (feed pipe ready to be placed in communication with high pressure port 43 and therefore to be fed with high pressure liquid) this angle having a value of about 120.

The right hand side of FIG. 2 simllarly shows the liquid delivery control rotating element 36, acting on exhaust valve 6, which bears against stationary element 29, said element 36 rotating in the clockwise direction. The angle B of rotation of the internal combustion engine corresponding to the closing of exhaust valve 6 is determined by the respective position of the low pressure port 46 and of the arcuate orifice 55, as indicated by FIG. 2 (discharge pipe 51 just going to be cut off from the low pressure port 46), this angle having a value of about 250.

It is advantageous to provide means for cancelling, at least approximately, the rocking torque exerted on the two delivery elements 35 and 36.

Such means many advantageously be made as follows:

Concerning delivery element 35, said means comprise a hydraulically balanced system including a spring and a shoe 56 subjected to a pressure equal to that which produces the rocking torque for said delivery element 35.

Concerning delivery element 36, the means in question comprise a hydraulically balanced system including a spring and a shoe 57 subjected to a pressure equal to that which produces the rocking torque of said delivery element 36.

Finally, it is necessary to provide, for driving hydraulic generator 7, a mechanism which is, at least during the starting of the engine, independent of the speed of rotation of said engine.

Of course, hydraulic generator 7 may be driven by an auxiliary motor wholly independent of the internal combustion engine (for instance, an auxiliary electric motor). However, it seems advantageous to make use of the arrangement illustrated by FIG. 1 and according to which hydraulic generator 7 comprises two driving shaft, to wit;

On the one hand, a main driving shaft 58 angularly coupled with the engine through a free wheel mechanism 59, and,

On the other hand, an auxiliary driving shaft 60 coupled with an auxiliary electric motor 61 through a free wheel mechanism 62.

Means are provided so that when the number of revolutions per minute of the engine is lower than a given minimum value, for instance when the internal combustion engine is starting, auxiliary electric motor 61 acts to drive hydraulic generator 7.

For this purpose the feed circuit of auxiliary electric motor 61 comprises:

A switch 63 operated by a tachometric system 64 which closes said switch 63 when the number of revolutions of the engine drops below a given value, and

A manually operated switch 65.

Starting is obtained in the following manner:

Manual switch 65 is closed, which causes current to be fed to auxiliary electric motor 61 (switch 63 being closed) which then drives hydraulic generator 7.

When the oil pressure reaches a value sufiicient to operate receivers 8 and 9, a monometric contact 66 causes a luminous signal 67 to be shutoff.

The starting gear of the engine can then be operated.

When the number of revolutions of the engine reaches the given minimum value, tachometric system 64 causes switch 63 to open, which cuts off the feed of current to auxiliary electric motor 61, hydraulic generator 7 being then driven by the internal combustion engine.

Up to now, reference has been made only to a single cylinder engine. If it is desired to use a multiple cylinder engine, it is possible to proceed in the same manner but it will be necessary to provide:

In the stationary element 28 of portion I of the distributor, as many inlet and outlet orifices as there are intakes valves, and

In the stationary element 29 of portion II of the distributor, as many inlet and outlet orifices as there are exhaust valves.

Concerning the advantages of the invention, FIG. 3

shows, by way of example, in solid lines a curve where the angular positions of the engine crankshaft have been plotted in abscissas, being measured from the upper dead center position, and where the lift H of one of the valves, for instance an intake valve, of this engine has been plotted in ordinates.

The curve thus obtained has an approximately trapezoidal shape and includes:

A straight line portion MN characterizing the opening of the valve, point M corresponding to an angular position of the crankshaft of about 20, whereas point N corresponds to a position of the crankshaft of about 120,

A horizontal straight line MP characterizing the time for which the valve remains open, point P corresponding to a position of the crankshaft of about 180, and

A straight line portion PQ characterizing the closing of the valve, point Q corresponding to a position of the crankshaft of about 240.

It will be noted that:

The slope of portion MN depends, in particular, upon the flow rate of the hydraulic generator, its delivery pressure and the strentgth of the valve spring,

The length of straight line portion MP depends, in particular, upon the arrangement of the ports and orifices in the distributor, and

The slope of straight line portion PQ depends, in particular, upon the strength of the valve spring.

In order to permit comparison, the dotted line in FIG. 3 illustrates the lifting motion of an intake valve in a conventional engine of the same type. Comparison between the two curves clearly shows the advantages resulting from the present invention.

Of course, the engine might be provided with one or several scavenging valves controlled by a device similar to that illustrated by the diagrams of this application.

In general manner, while the above description discloses What are deemed to be practical and efiicient embodiments of the present invention, said invention is not limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of the invention as comprehended within the scope of the appended claims.

What I claim is:

1. An internal combustion engine which comprises, in combination:

a cylinder forming a combustion chamber,

a valve in the Wall of said cylinder,

a hydraulic generator for delivering in a continuous manner a liquid under pressure,

a volumetric hydraulic receiver operative by liquid from said generator, said receiver including a housing and a member fitting movably in said housing in one direction movable by liquid under pressure fed to said receiver,

interconnecting means between said member and said valve for opening said valve in response to the displacement of said member in said direction,

resilient means for urging said valve toward the closed position thereof,

a hydraulic distributor including a stationary casing having its inner surface in the form of a surface of revolution about a fixed axis and having an inner projection of revolution about said axis, this projection having two side faces perpendicular to said axis and polished to form slides,

a pair of elements, a first one and a second one, respectively, rotatable in said casing coaxially therewith and driven in rotation therein by the internal combustion engine, said elements having polished faces forming slides adapted to cooperate respectively with the slides formed by said opposed faces of said casing inner projection,

a pipe leading from said hydraulic generator to the inside of said casing on the side of the first of said rotatable elements opposed to that along which said first rotatable element is slidable along said casing inner projection,

said first rotatable element being provided with a port extending from one side to the other thereof and forming a groove in the form of a portion of a circle about the axis of said first rotatable element,

said inner projection of said casing being provided with an arcuate orifice adapted to communicate with said port for a portion of the rotation of said first rotatable element,

a pipe extending from said arcuate orifice to said hydraulic receiver housing,

said inner projection of said casing being provided with an arcuate orifice on the side thereof in sliding contact with said second rotatable element,

a pipe extending from said hydraulic receiver housing to said last mentioned arcuate orifice,

said second rotatable element being provided with a port extending from one side to the other thereof and forming a groove in the form of a portion of a circle about the axis of said second rotatable element, said last mentioned port being adapted to cooperate with said last mentioned arcuate orifice,

and a discharge pipe leading out from said last mentioned port.

2. An internal combustion engine according to claim 1 further comprising means for cancelling, at least approximately, the rocking torque exerted on said delivery element.

3. An internal combustion engine according to claim 2 wherein said last mentioned means comprise:

a hydraulically balanced system including a spring and a shoe subjected to a pressure equal to that which produces the rocking torque on said delivery element.

4. An internal combustion engine according to claim 1 further characterized in that the hydraulic generator comprises two driving shafts, to Wit:

on the one hand, a main driving shaft angularly coupled with the internal combustion engine with a free Wheel mechanism interposed between said engine and said main driving shaft,

on the other hand, an auxiliary driving shaft,

an auxiliary electric motor,

a free Wheel mechanism interposed between said auxiliary motor and said auxiliary driving shaft,

means capable, when the number of revolutions per minute of the internal combustion engine is lower than a given minimum value, of coupling said auxiliary electric motor with said hydraulic generator for driving it.

5. An internal combustion combination:

a cylinder forming a combustion chamber,

a valve in the wall of said cylinder,

a hydraulic generator for delivering in a continuous manner a liquid under pressure,

a volumetric hydraulic receiver operative by liquid from said generator, said receiver including a housing and a member fitting movably in said housing in one direction movable by liquid under pressure fed to said receiver,

interconnecting means between said member and said valve for opening said valve in response to the displacement of said member in said direction,

resilient means for urging said valve toward the closed position thereof,

a hydraulic distributor interposed between said hydraulic generator and said hydraulic receiver,

two driving shafts for said hydraulic generator, to wit,

on the one hand, a main driving shaft angularly coupled with the internal combustion engine with a free Wheel mechanism interposed between said engine and said main driving shaft engine which comprises, in

7 0n the other hand, an auxiliary driving shaft, an auxiliary electric motor,

a free wheel mechanism interposed between said auxiliary motor and said auxiliary driving shaft, means capable, when the number of revolutions per minute of the internal combustion engine is lower than a given minimum value, of coupling said auxiliary electric motor with said hydraulic generator for driving it.

References Cited UNITED STATES PATENTS 1,473,077 11/1923 Bull 123-90 2,090,877 8/1937 Small "123-90 2,915,052 12/1959 Gullen 123 90 2,962,013 11/1960 Reggio 123 92 AL LAWRENCE SMITH, Primary Examiner. 

1. AN INTERNAL COMBUSTION ENGINE WHICH COMPRISES, IN COMBINATION: A CYLINDER FORMING A COMBUSTION CHAMBER, A VALVE IN THE WALL OF SAID CYLINDER, A HYDRAULIC GENERATOR FOR DELIVERING IN A CONTINUOUS MANNER A LIQUID UNDER PRESSURE, A VOLUMETRIC HYDRAULIC RECEIVER OPERATIVE BY LIQUID FROM SAID GENERATOR, SAID RECEIVER INCLUDING A HOUSING AND A MEMBER FITTING MOVABLY IN SAID HOUSING IN ONE DIRECTION MOVABLE BY LIQUID UNDER PRESSURE FED TO SAID RECEIVER, INTERCONNECTING MEANS BETWEEN SAID MEMBER AND SAID VALVE FOR OPENING SAID VALVE IN RESPONSE TO THE DISPLACEMENT OF SAID MEMBER IN SAID DIRECTION, RESILIENT MEANS FOR URGING SAID VALVE TOWARD THE CLOSED POSITION THEREOF, A HYDRAULIC DISTRIBUTOR INCLUDING A STATIONARY CASING HAVING ITS INNER SURFACE IN THE FORM OF A SURFACE OF REVOLUTION ABOUT A FIXED AXIS AND HAVING AN INNER PROJECTION OF REVOLUTION ABOUT SAID AXIS, THIS PROJECTION HAVING TWO SIDE FACES PERPENDICULAR TO SAID AXIS AND POLISHED TO FORM SLIDES, A PAIR OF ELEMENTS, A FIRST ONE AND A SECOND ONE, RESPECTIVELY, ROTATABLE IN SAID CASING COAXIALLY THEREWITH AND DRIVEN IN ROTATION THEREIN BY THE INTERNAL COMBUSTION ENGINE, SAID ELEMENTS HAVING POLISHED FACES FORMING SLIDES ADAPTED TO COOPERATE RESPECTIVELY WITH THE SLIDES FORMED BY SAID OPPOSED FACES OF SAID CASING INNER PROJECTION, A PIPE LEADING FROM SAID HYDRAULIC GENERATOR TO THE INSIDE OF SAID CASING ON THE SIDE OF THE FIRST OF SAID ROTATABLE ELEMENTS OPPOSED TO THAT ALONG WHICH SAID FIRST ROTATABLE ELEMENT IS SLIDABLE ALONG SAID CASING INNER PROJECTION, SAID FIRST ROTATABLE ELEMENT BEING PROVIDED WITH A PORT EXTENDING FROM ONE SIDE TO THE OTHER THEREOF AND FORMING A GROOVE IN THE FORM OF A PORTION OF A CIRCLE ABOUT THE AXIS OF SAID FIRST ROTATABLE ELEMENT, SAID INNER PROJECTION OF SAID CASING BEING PROVIDED WITH AN ARCUATE ORIFICE ADAPTED TO COMMUNICATE WITH SAID PORT FOR A PORTION OF THE ROTATION OF SAID FIRST ROTATABLE ELEMENT, A PIPE EXTENDING FROM SAID ARCUATE ORIFICE TO SAID HYDRAULIC RECEIVER HOUSING, SAID INNER PROJECTION OF SAID CASING BEING PROVIDED WITH AN ARCUATE ORIFICE ON THE SIDE THEREOF IN SLIDING CONTACT WITH SAID SECOND ROTATABLE ELEMENT, A PIPE EXTENDING FROM SAID HYDRAULIC RECEIVER HOUSING TO SAID LAST MENTIONED ARCUATE ORIFICE, SAID SECOND ROTATABLE ELEMENT BEING PROVIDED WITH A PORT EXTENDING FROM ONE SIDE TO THE OTHER THEREOF AND FORMING A GROOVE IN THE FORM OF A PORTION OF A CIRCLE ABOUT THE AXIS OF SAID SECOND ROTATABLE ELEMENT, SAID LAST MENTIONED PORT BEING ADAPTED TO COOPERATE WITH SAID LAST MENTIONED ARCUATE ORIFICE, AND A DISCHARGE PIPE LEADING OUT FROM SAID LAST MENTIONED PORT.
 5. AN INTERNAL COMBUSTION ENGINE WHICH COMPRISES, IN COMBINATION: A CYLINDER FORMING A COMBUSTION CHAMBER, A VALVE IN THE WALL OF SAID CYLINDER, A HYDRAULIC GENERATOR FOR DELIVERING IN A CONTINUOUS MANNER A LIQUID UNDER PRESSURE, A VOLUMETRIC HYDRAULIC RECEIVER OPERATIVE BY LIQUID FROM SAID GENERATOR, SAID RECEIVER INCLUDING A HOUSING AND A MEMBER FITTING MOVABLY IN SAID HOUSING IN ONE DIRECTION MOVABLE BY LIQUID UNDER PRESSURE FED TO SAID RECEIVER, INTERCONNECTING MEANS BETWEEN SAID MEMBER AND SAID VALVE FOR OPENING SAID VALVE IN RESPONSE TO THE DISPLACEMENT OF SAID MEMBER IN SAID DIRECTION, RESILIENT MEANS FOR URGING SAID VALVE TOWARD THE CLOSED POSITION THEREOF, A HYDRAULIC DISTRIBUTOR INTERPOSED BETWEEN SAID HYDRAULIC GENERATOR AND SAID HYDRAULIC RECEIVER, TWO DRIVING SHAFTS FOR SAID HYDRAULIC GENERATOR, TO WIT, ON THE ONE HAND, A MAIN DRIVING SHAFT ANGULARLY COUPLED WITH THE INTERNAL COMBUSTION ENGINE WITH A FREE WHEEL MECHANISM INTERPOSED BETWEEN SAID ENGINE AND SAID MAIN DRIVING SHAFT, ON THE OTHER HAND, AN AUXILIARY DRIVING SHAFT, AN AUXILIARY ELECTRIC MOTOR, A FREE WHEEL MECHANISM INTERPOSED BETWEEN SAID AUXILIARY MOTOR AND SAID AUXILIARY DRIVING SHAFT, MEANS CAPABLE, WHEN THE NUMBER OF REVOLUTIONS PER MINUTE OF THE INTERNAL COMBUSTION ENGINE IS LOWER THAN A GIVEN MINIMUM VALUE, OF COUPLING SAID AUXILIARY ELECTRIC MOTOR WITH SAID HYDRAULIC GENERATOR FOR DRIVING IT. 